1. Field of the Invention
The present invention relates to a flat display technology, and more particularly to a method for driving a liquid crystal display (LCD) panel and an LCD using the same.
2. Description of Related Art
In recent years, with great advance in the fabricating techniques of opto-electronics and semiconductor devices, flat panel displays (FPDs) have been vigorously developed. Among the FPDs, a liquid crystal display (LCD) has become the mainstream display product due to its advantages of outstanding space utilization efficiency, low power consumption, free radiation, and low electrical field interference. The LCD includes an LCD panel and a backlight module in most cases. Since the LCD panel can not emit light, the backlight module disposed underneath the LCD panel is required to function as a planar light source to provide the LCD panel with light on which images being displayed.
In a conventional LCD, the backlight module acting as the planar light source required by the LCD panel generally provides a white light, and the LCD can then display different colors through a color filter disposed on each pixel region in the LCD panel. In view of the above, red, green, and blue color filters must be disposed on each of the pixel regions, thus increasing manufacturing costs and reducing the transmittance of each pixel after the white light passes through the color filters.
As a result, in the recently-designed LCD, a light emitting diode (LED) backlight source is generally utilized to replace the traditional white backlight source to display the colors of the pixels. In other words, the colors are mixed on an axis of space. Specifically, three sub-pixels of red, green and blue colors mixed together within viewing angles of human beings are replaced by mixing the three sub-pixels on an axis of time. That is to say, the red, green, and blue colors emitted by the LED backlight source are rapidly switched within a range of time of visual perception of human beings.
For instance, if dynamic images are displayed at the frequency of 60 frames per second, a refresh rate of the LCD panel must be increased from 16.67 ms ( 1/60 second) to 5.56 ms ( 1/180 second) given that the red, green and blue color images are rapidly switched on the axis of time. Said driving method is referred to as a color sequential method by which the color filters are not required to be disposed on each of the pixel regions within the LCD panel, and thereby increasing the transmittance of each pixel.
Nevertheless, a response speed of liquid crystal molecules of each pixel in the LCD panel is still not sufficient enough at this current stage. Therefore, when the same data signals are provided to each pixel of the LCD panel, the luminance of the last row pixels of the LCD is reduced in comparison with the luminance of the first row pixels of the LCD, which results in uneven brightness. A problem of poor image quality on a color sequential LCD accordingly arises. As such, the issue of the uneven brightness is often encountered in normal color sequential LCDs.